#include <stdio.h>

struct Books
{
  /* data */
  char title[50];
  char author[50];
  char subject[100];
  int book_id;
} book = {
    "C语言", "ALVIN", "编程语言", 100001};

int main()
{
  printf("title: %s\n author: %s\n subject: %s\n book_id: %d\n", book.title, book.author, book.subject, book.book_id);
  return 0;
}